We have
[tex]x^2-24x=-50[/tex]We need to complete the square
[tex]a^2+2ab+b^2[/tex]in thi case
a=x
2ab=-24x
2xb=-24x
b=-12
[tex]\begin{gathered} x^2-24x+144=-50+144 \\ (x-12)^2=94 \end{gathered}[/tex]Then for each solution we have
[tex]\begin{gathered} x-12=\pm\sqrt[]{94} \\ \end{gathered}[/tex][tex]\begin{gathered} x_1=12-\sqrt[]{94} \\ x_2=12+\sqrt[]{94} \end{gathered}[/tex]